[kvm-unit-tests,v6,0/4] x86: Add test cases for LAM

Message

Binbin Wu Jan. 22, 2024, 8:53 a.m. UTC

Intel Linear-address masking (LAM) [1], modifies the checking that is applied to
*64-bit* linear addresses, allowing software to use of the untranslated address
bits for metadata.

The patch series add test cases for KVM LAM:

Patch 1 makes change to allow setting of CR3 LAM bits in vmlaunch tests.
Patch 2~4 add test cases for LAM supervisor mode and user mode, including:
- For supervisor mode
  CR4.LAM_SUP toggle
  Memory/MMIO access with tagged pointer
  INVLPG
  INVPCID
  INVVPID (also used to cover VMX instruction VMExit path)
- For user mode
  CR3 LAM bits toggle 
  Memory/MMIO access with tagged pointer

[1] Intel ISE https://cdrdv2.intel.com/v1/dl/getContent/671368
    Chapter Linear Address Masking (LAM)

---
Changelog
v6
- Fix a comment [Chao]
- Use write_cr4() instead of write_cr4_safe() to catch unexpected exceptions. [Chao]
- Use a non-canonical address that will be canonical if LAM applied as the
  tagged address in the descriptor of invvpid. [Chao]
- Add a reviewed-by from Chao in patch 4.

v5
- https://lore.kernel.org/kvm/[e-mail]/

Binbin Wu (3):
  x86: Allow setting of CR3 LAM bits if LAM supported
  x86: Add test cases for LAM_{U48,U57}
  x86: Add test case for INVVPID with LAM

Robert Hoo (1):
  x86: Add test case for LAM_SUP

 lib/x86/processor.h |  15 +++
 x86/Makefile.x86_64 |   1 +
 x86/lam.c           | 319 ++++++++++++++++++++++++++++++++++++++++++++
 x86/unittests.cfg   |  10 ++
 x86/vmx_tests.c     |  52 +++++++-
 5 files changed, 395 insertions(+), 2 deletions(-)
 create mode 100644 x86/lam.c


base-commit: 3c1736b1344b9831f17fbd64f95ea89c279564c6